window.onload=function(){
	var input=document.getElementById("linkToInput");
	var divIt=document.getElementsByClassName("link-to-input")[0];
	var comment=document.getElementById("add-comment");
	input.addEventListener("click",function(){
		divIt.classList.add("hidden");
		comment.classList.remove("hidden");
		show(comment,170);
	})
	//  需要手指按下事件----TODO，  失去焦点，隐藏评论框
	window.addEventListener("mousedown",function(e){
		//  TODO
	})
}
function show(obj,hei){
	var height=0;
	var time=setInterval(function(){
		obj.style.height=height+'px';
		height=obj.clientHeight;
		if (height>=hei) {
			clearInterval(time);
		}else{
			height+=10;
		}
	},8)
}